Water Skiing Disk

ABSTRACT

A water skiing disk that is used by a water skier at slow speeds does not require bindings or other similar types of foot constraints and has a large exterior diameter dimension to hold up one or more skiers on the water at slow speeds while being light weight and easily transported by a single person.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to a water skiing disk that has a large exterior diameter dimension to hold up one or more skiers on the water at slow speeds. Because the water skiing disk is used at slow speeds, it does not require bindings or other similar types of foot constraints to secure the water skier's feet to the disk. Although the disk has a large diameter dimension, due to the novel construction of the disk, the weight of the disk is reduced and is easily transported by a single person.

2. Description of the Related Art

Conventional water skiing by a person involves the person wearing one or more skis on their feet with the person being towed by a boat at a substantial speed. The substantial towing speed is needed to keep the person afloat on the skis. Wider skis have been developed, for example wake boards, which enable the skier to be towed behind a boat at a reduced speed while remaining afloat. However, whether skiing on conventional skis or on a wake board, the speed required of the boat towing the skier is sufficient to require that the water skis or wake board be secured to the skier's feet.

In conventional water skiing there is a significant force exerted on the skier by the tow rope of the boat pulling the skier. The force is due to the speed required to keep the skier afloat, and by the resistance exerted by the water on the ski or wake board moving through the water. The speed of the boat pulling the skier when water skiing or wake boarding is a primary factor in the difficulty experienced by a novice learning to water ski. In addition, the speed required of the boat towing the water skier is also a primary factor in the fatigue of the water skier, whether a novice skier or an experienced skier.

SUMMARY OF THE INVENTION

The water skiing disk of the present invention overcomes disadvantages associated with conventional water skiing and water wake boarding by providing a disk of unique construction that can support a water skier on the water while being towed by a boat moving at a substantially decreased speed from that required when water skiing or wake boarding. The unique construction of the disk has a large diameter dimension that enables the water skier to stay afloat at reduced skiing speeds, and also enables more than one water skier to use the disk at a time. In addition, the unique construction of the disk which allows it to support a water skier at a significantly reduced speed also eliminates the need for foot bindings on the disk. This enables the water skier to move their feet to substantially any positions on the disk that are comfortable to the water skier when using the disk. Although the water skiing disk of the invention has an enlarged diameter dimension, the unique construction of the disk also reduces the weight of the disk and thereby enables it to be easily transported by a single person.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the water skiing disk of the invention are explained in the following detailed description of the disk and in the drawing figures.

FIG. 1 is a plan view of the first, bottom surface of the water skiing disk of the invention.

FIG. 2 is a side view of the water skiing disk of the invention.

FIG. 3 is a side sectioned view of the water skiing disk.

FIG. 4 is a plan view of the second, top surface of the water skiing disk showing the position of a vent hole that is used in constructing the disk.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 is a plan view of a bottom, first surface of the water skiing disk of the present invention 12. In the preferred embodiment, the disk 12 has an exterior diameter dimension of 47 inches. It is contemplated that varying the exterior diameter dimension of the disk by plus or minus 2 inches from the preferred 47 inch exterior diameter of the disk would enable the disk to be used with substantially the same results in water skiing as the preferred 47 inch diameter disk. However, through experimentation it has been determined that the best results in water skiing with the disk 12 are achieved when the disk has a 47 inch diameter dimension combined with the other particular dimensions of the disk to be described.

As seen in FIG. 1, the disk 12 has a circular outer peripheral edge 14. There are no protrusions or obstructions on the circular outer edge 14 of the disk 12. FIG. 1 shows a first, bottom surface 18 of the disk 12. It can be seen in FIG. 1 that there are no holes or other obstructions through the disk within the disk outer edge 14.

Referring to FIG. 2, the outer peripheral edge 14 has a center axis 16 that defines mutually perpendicular axial and radial directions relative to the disk. The disk 12 has a second, top surface 22 that is opposite the first, bottom surface 18. The disk 18 is specifically designed for water skiing on the first surface 18. It can also be seen in FIG. 2 that both the first surface 18 and second surface 22 of the disk are smooth, continuous disk surfaces with there being no obstructions or protrusions on the surfaces within the disk outer peripheral edge 14.

The particular cross-section configuration of the disk shown in FIG. 2 results in the synergistic ability of the disk to support one or more water skiers when the skiers are towed on the disk 12 at a reduced speed over the water. The synergistic effect of the particular exterior cross-section configuration of the disk 12 enables a water skier to easily get up on the water using the disk when towed at a reduced speed, and to remain on the water using the disk when towed at a reduced speed. Because the particular configuration of the first, bottom surface 18 provides the stability of the disk as it is towed at slow speed over the water, the exterior configuration of the first surface 18 will be described in detail. It should be understood that the exterior configuration of the second surface 22 also contributes to the beneficial feature of the reduced weight of disk 12 which contributes to the ease and safety of using the disk 12.

Referring to FIGS. 1 and 3, the first, bottom disk surface 18 comprises a circular center section 24 that extends radially outwardly from the center axis 16 to a radius dimension of from 18 inches to 22 inches from the center axis 16. Better performance is achieved when the radius of the center section 24 of the first disk surface 18 is in a range of from 19 inches to 19.5 inches. In the preferred embodiment of the invention, the radius of the circular center section is 19.47 inches, and the center section is flat and is positioned in a plane that is perpendicular to the center axis 16.

The axial distance between the first and second surfaces 18, 22 at the center axis 16 is preferably in a range of 1 to 2 inches. In a more preferred embodiment, the axial thickness between the first surface 18 and the second surface 22 at the center axis 16 is 1.5 inches. In the preferred embodiment of the invention, the axial thickness between the first surface 18 and the second surface 22 at the center axis 16 is 1.436 inches.

Outside of the center section 24 of the first surface 18 of the disk, the disk bottom surface has a first annular intermediate section 26. The first annular intermediate section 26 of the first surface 18 extends radially outwardly from the first center section 24 to a radius of from 2 inches to 6 inches from the center section. In the preferred embodiment of the invention, the first annular intermediate section 26 of the first surface 18 extends radially outwardly 4 inches from the preferred radial dimension of 19.47 inches of the first center section 24.

In addition to the above, the first annular intermediate section 26 of the first surface 18 has a radius of curvature in a range of from 225 inches to 235 inches. In the preferred embodiment of the invention, the radius of curvature of the first annular intermediate section 26 is 275.4 inches.

The first 18 disk surface also has an annular outer section 28. The annular outer section 28 extends radially outwardly from the annular intermediate section 26 to the outer peripheral edge 14 of the disk, or for a radial distance of substantially 1 inch. In the preferred embodiment of the invention, the first annular outer section 28 will have a radial dimension of 0.53 of an inch from the first annular intermediate section 26 of the preferred embodiment to the outer peripheral edge 14 of the disk.

In addition, the first annular outer section 28 of the disk has a radius of curvature in a range of from 0.35 of an inch to 0.40 of an inch. In the preferred embodiment of the invention, the radius of curvature of the first annular outer section 28 is 0.375 of an inch.

The second disk surface 22 of the disk 12 is designed as the top surface of the disk that will support the skier. The second surface 22 has a continuous, convex surface that extends from the center axis 16 of the disk out to the outer edge 14 of the disk. The second surface 22 extends from the center axis 16 to a radial dimension of 20 to 23 inches. In the preferred embodiment, the radial dimension of the continuous, convex top surface is substantially 23 inches.

In addition to the radial dimension, the second, top surface 22 of the disk 12 has a radius of curvature in a range of from 500 inches to 600 inches. In the preferred embodiment of the invention, the radius of curvature of the top, second surface 22 is 552 inches.

The second disk surface 22 also has an annular outer section 32 that is substantially a mirror image of the first surface annular outer section 28. The annular outer section 32 of the second, top surface 22 extends around the outer peripheral edge 14 of the disk and has a radial width dimension of substantially one inch. In the preferred embodiment of the invention, the second annular outer section 32 of the top, second surface 22 has a radial dimension of 0.53 of an inch.

The particular dimensions of the disk 12 discussed above result in the synergistic ability of the disk to raise one or more skiers upon the water and keep the skiers on the water with a reduced speed of a towing boat. The particular dimensions of the disk 12 discussed above enable even a novice user of the disk to easily get up on the water and stay on the water skiing at an operating speed as slow as 12-14 miles per hour.

Referring to FIG. 3, the disk in its preferred form is constructed of a hollow plastic shell. The shell is comprised of a first saucer shaped piece 42 that defines the first, bottom surface 18 of the disk, and a second saucer shaped piece 44 that defines the second, top surface 22 of the disk. The two pieces 42, 44 are formed of plastic by rotational molding. Other means of forming plastic, for example blow molding, could also be used. However, the rotational molding process is preferred in performing the two pieces 42, 44 of the outer shell of the disk 12.

The top piece 22 is formed with a vent hole 46. The vent hole in the preferred embodiment has a 1 inch diameter. The preferred position of the vent hole 46 is off center as shown in FIG. 4. The vent hole 46 is employed in injecting foam pellets into the interior of the disk between the two disk pieces 42, 44. The foam pellets are also heated and rotary molded to form a rigid foam interior core 48 between the two pieces 42, 44 of the disk.

In the preferred embodiment of the invention, the rotationally molded plastic that forms the two pieces 42, 44 on the opposite sides of the disk 12 is a polyethylene such as the Surpass® polyethylene MDPE RMs 539 produced by Nova Chemicals®. The foam employed in producing the rigid foam core 48 of the disk 12 is preferably rotational molded in the interior of the disk 12 from micro pellets at 10 pounds per cubic foot.

The above construction results in a weight of less than 30 pounds for the 47 inch diameter disk 12. In the preferred embodiment, the weight of the disk is 24 pounds. This light weight not only makes the disk easily transportable, but also contributes to the safety of the disk should a person be struck by the disk when skiing.

Although the disk of the invention has been described above by reference to a particular embodiment of the disk, variations and modifications could be made to the disk described without departing from the intended scope of the following claims. 

1) A water skiing disk comprising: first and second disk surfaces are opposite sides of the disk, the first and second disk surfaces with a diameter of from 40 to 50 inches and having a circular outer edge with a center axis that defines mutually perpendicular axial and radial directions relative to the disk, the first and second disk surfaces having no obstructions on the surfaces; the disk having an axial thickness between the first and second disk surfaces at the center axis of from 1 inch to 2 inches; the first disk surface having circular center section that extends radially outwardly from the center axis to a radius of 18 inches to 22 inches, the center section being substantially flat; the first disk surface having annular intermediate section that extends radially outwardly from the center section to a radius of from 2 inches to 6 inches from the center section, the intermediate section having a large radius of curvature; and, the first disk surface having annular outer section that extends radially outwardly from the intermediate section to the outer edge, the outer section having a small radius of curvature that is smaller than the large radius of curvature. 2) The disk of claim 1, further comprising: the large radius of curvature being from 225 inches to 325 inches; and, the small radius of curvature being from 0.35 of an inch to 0.40 of an inch. 3) The disk of claim 1, further comprising: the circular center section of the first disk surface extending radially outwardly from the center axis to a radius of substantially 19 inches; the annular intermediate section of the first disk surface extending radially outwardly from the center section to a radius of substantially 4 inches from the center section; and, the annular outer section of the first disk surface extending radially outwardly from the intermediate section to a radius of substantially 1 inch from the intermediate section. 4) The disk of claim 3, further comprising: the axial thickness of the disk at the center axis being substantially 1 inch. 5) The disk of claim 1, further comprising: the first and second disk surfaces being on a plastic outer shell with a hollow interior; and, a hardened foam filling the hollow interior. 6) The disk of claim 5, further comprising: the foam completely filling the hollow interior of the outer shell. 7) A water skiing disk comprising: first and second disk surfaces on opposite sides of the disk, the first and second disk surfaces having a diameter dimension of substantially 47 inches and a circular outer edge with a center axis that defines mutually perpendicular axial and radial directions relative to the disk, the first and second disk surfaces having substantially convex configurations, the first disk surface having a circular center section that extends radially outwardly from the center axis to a radius of substantially 19.5 inches and being substantially flat, the first disk surface having an annular intermediate section that extends radially outwardly from the center section to a radius of substantially 4.0 inches from the center section and having a radius of curvature of substantially 275.4 inches, and the first disk surface having an annular outer section that extends radially outwardly from the intermediate section to the outer edge and having a radius of curvature of substantially 0.375 of an inch. 8) The disk of claim 7, further comprising: the second disk surface extending radially outwardly from the center axis to the outer edge and having a radius curvature of substantially 552 inches. 9) The disk of claim 7, further comprising: the first and second disk surfaces being continuous surfaces within the outer edge with there being no obstructions on the first and second disk surfaces within the outer edge. 10) The disk of claim 7, further comprising: the first and second disk surfaces being continuous convex surfaces within the outer edge with there being no hole through the disk within the outer edge. 11) The disk of claim 7, further comprising: the disk weighing less than 30 pounds. 12) The disk of claim 7, further comprising: the disk weighing substantially 24 pounds. 13) The disk of claim 7, further comprising: a hollow plastic outer shell with the first and second disk surfaces being on opposite sides of the shell. 14) The disk of claim 13, further comprising: a hardened foam filling the shell. 15) A water skiing disk comprising: an outer plastic hollow shell having opposite first and second disk surfaces and a circular outer peripheral edge around the first and second surfaces, the circular outer peripheral edge having a diameter dimension of 47 inches, the second disk surface having a convex configuration with a radius of curvature of from 500 inches to 600 inches, the first disk surface having a circular center section that is flat, the first disk surface having an annular intermediate section that extends around the center section and has a radius of curvature of from 250 inches to 300 inches, and the first disk surface having an annular outer section that extends around the intermediate section and extends to the outer peripheral edge and has a radius of curvature from 0.35 inches to 0.40 inches. 16) The disk of claim 15, further comprising: the radius of curvature of the second disk surface being substantially 552 inches, the radius of curvature of the first disk surface intermediate section being 275.4 inches, and the radius of curvature of the first disk surface outer section being 0.375 of an inch. 17) The disk of claim 15, further comprising: the first and second disk surfaces being continuous surfaces within the outer edge with there being no obstructions on the first and second disk surfaces within the outer edge. 18) The disk of claim 15, further comprising: the first and second disk surfaces being continuous surfaces within the outer edge with there being no hole through the disk within the outer edge. 19) The disk of claim 15, further comprising: the disk weighing less than 30 pounds. 20) The disk of claim 15, further comprising: a hollow plastic outer shell with the first and second disk surfaces being on opposite sides of the shell. 21) The disk of claim 20, further comprising: a hardened foam filling the shell. 